The modern-style house on a quiet leafy street in southwest Minneapolis has a mysterious air. Tall and tucked into its site, it resembles a geometry diagram, with squares jutting out, a bank of soaring narrow windows and a windowless turret that resembles a white grain silo.

Walk up the winding stone steps to the front door, and you're not quite sure what to do next. The double door has no knobs or handles, and there's no sign of a knocker or doorbell.

Then you spot a sculptural metal circle, like a Ferris wheel with bells hanging from it, near the entrance. The bells herald your arrival, but the only way to enter the house is to be welcomed in by someone on the other side of the door.

Architect Benjamin Gingold designed the distinctive house for himself and his family in the late 1950s. Completed in 1959, it was so unusual that it attracted attention from the New York Times and Progressive Architecture magazine.

The 4,220-square-foot house spans four levels and boasts many dramatic features, including a living room with 18-foot ceilings, a travertine stone raised platform with an arched cylindrical fireplace, and abundant mahogany paneling and built-ins.

Then there's the staircase inside that turret: a four-story spiral lit by a circular skylight with a curving handrail that "winds like the peel of an orange from top to bottom," as Gingold described it, according to "Minnesota Modern" by local architectural historian Larry Millett.

Gingold, a Yale-trained architect who did mostly commercial projects, also taught at the University of Minnesota under Ralph Rapson. In his house, he combined Bauhaus influences with architectural ideas he absorbed during a sabbatical in Greece, particularly on the island of Mykonos. There's even a touch of Spanish architect Antonio Gaudi in the tile mosaic master bath with double brass sinks, a circular shower and a door behind the tub that opens to reveal a fireplace in the hallway.

The combination was irresistible to Bouky Labhard when she and her late husband bought the house in 1970. A native of Greece who studied architecture in Switzerland, Labhard and her Swiss-American husband, Fred, were moving to the Twin Cities, with two young daughters in tow, for Fred's job with Toro Corp.

They had a difficult time finding the right house. "We saw beautiful houses but with small rooms," Bouky recalled. "We brought our furniture, some very large pieces, family antiques, and we were looking for a space where they looked right."

'This is our home'

Then Fred toured the Gingold house and brought Bouky with him for a second look. "My husband told me I would fall in love with the house," she recalled. "I walked inside, took one look, turned to him and said, 'This is our home.' "

She loved the way the exterior nestled into the terrain. "It's coming out of the earth gently, without screaming," she said. And she loved the open floor plan and the way rooms were designed to maximize views of the outdoors — the bedrooms felt like being in a treehouse.

The house was sophisticated, but it was also a big hit with the Labhards' young daughters and their friends, with its balcony overlooking the living room, secret doors and cabinets, a "cat house" tucked under the pantry, buttons that open the mysterious front door from every floor of the house, and that undulating staircase.

"Kids could play hide-and-seek and would beg to have sleepovers" in the unusual dwelling, she recalled. "It's unexpected to see in Minneapolis."

Gingold disliked knobs, so many of the cabinets open to the touch. But he did like brass and used it abundantly throughout the home.

The architect lived in his creation only two years, selling it to a fashion designer after he divorced his first wife, and later moving to England. The Labhards were only the third owners.

Gingold hadn't finished the lower level, so the Labhards did, turning it into a mahogany-paneled family room/bedroom with two Murphy beds, a small office and a bathroom. Over the years, it's served as a guest suite, a playroom, a teen hangout and an apartment for Bouky's mother.

Many ahead-of-its-time features

Other than that enhancement, they tried to preserve Gingold's original vision for his home. "It's exactly the way he designed it," said Bouky. "We loved it and respected it."

The house has many ahead-of-its-time features including an open floor plan, a big kitchen with a center island, recessed can lighting and a big walk-in closet in the master bedroom.

The kitchen's original textured travertine floors and clean-lined mahogany cabinets are intact and would look at home in a trophy kitchen of today. The previous owner had replaced Gingold's marble countertops with '60s Formica, which the Labhards updated with honed granite.

Once in the early 1980s, the Labhards had unexpected visitors — "a refined gentleman and a woman" who showed up at their door. It was Gingold and his first wife, Sally, who had helped him supervise the building of the house while they were married.

"He was so attached to the house," Bouky recalled.

Gingold and his ex-wife told her how they had instructed the workers not to make perfect corners but to "allow your hand to caress the cement" in forming the curving balcony and staircase.

She showed Gingold the now completed lower level. "He was very pleased with the way we finished it," she said.

Bouky, a passionate gardener, has created an "architectural garden" with curving stone paths, lush vegetation and a patio, trying to fulfill Gingold's vision of his home surrounded by trees and grasses. "It was his dream," she said.

Now, after almost 47 years in the house, she's ready to downsize to a condo, do some traveling and devote more time to photography.

"I am welcoming the next phase of my life," she said. "This house has kept me happy for 47 years. It brings joy to all who step into it. My biggest hope is that the new owner will have the happiness we had here."

Bill Sweatt of Edina Realty has the listing, 612-275-2831, There will be an open house 1 to 4 p.m. on May 28, 4745 Girard Av. S., Minneapolis.

Kim Palmer • 612-673-4784